I am just trawling through the "unanswered posts" section and came across your pic. I guess you took the photo on a dull day (very common in Scotland!) and the pic is a little too dark IMHO. Try adjusting levels in Photoshop or whatever software you use. I think the histogram is probably showing the highlights don't reach the right edge of the chart so in "adjust levels" slide the pointer to the left until it meets the end of the spread. That should improve the pic. Nice framing by the way.